Well, another weekend, and another project. This time, once I got to my lab, I had to debug a DIY usb dongle (avr based, stuffed with vusb framework). And… Well, things didn’t work out of the box this time and I got a bunch of glitches.
So, I decided to finally make a dongle for sniffing usb transactions. The idea was flying around for some time, and it seems to me someone has already done something similar at HaD. Well, I was too lazy to search.
It was a pretty simple one – just 2 ports, some pins for easy oscilloscope access and three leds, activated via a jumper. One for power line, and 2 for D+ D- lines.
This time, as recommended by a friend of mine I didn’t remove the toner (Thanks, Inky!). Once the thing was ready, I applied some urethane spray, so that the whole thing would last longer.
As usual here go the kicad schematics and pcb layout files, including ready to pring PostScript, if you’re gonna make one for yourself: sniffo.tar.gz